Related Experiment Video
Updated: Jun 7, 2026
The Identification of Sea Lamprey Pheromones Using Bioassay-Guided Fractionation
Published on: July 17, 2018
3D models of lamprey progesterone receptor complexed with progesterone, 7α-hydroxy-progesterone and
Michael E Baker1, Paiyuam Asnaashari, David J Chang
1Department of Medicine, 0693, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0693, USA. mbaker@ucsd.edu
Abstract:
Sea lamprey, a basal vertebrate, contains a progesterone receptor [PR]. An unusual property of lamprey is that gonadotropin-releasing hormone induces synthesis of 15α-hydroxy-progesterone [15α-OH-P] instead of progesterone. There also is indirect evidence for 7α-OH-P in lamprey serum. To determine if there is a structural basis for the binding of 7α-OH-P and 15α-OH-P to lamprey PR, we constructed 3D models of the lamprey PR complexed with progesterone, 7α-OH-P and 15α-OH-P. These 3D models reveal that Met-277 in lamprey PR has a specific interaction with the 15α-hydroxyl on 15α-OH-P and with Met-192, which also contacts the 15α-hydroxyl group. We also find that 7α-OH-P has favorable contacts with side-chains in lamprey PR. BLAST searches reveal that Met-277 on lamprey PR is unique among vertebrate PRs. This unique site on lamprey PR could be a target for compounds to control reproduction in sea lamprey, an environmental pest in Lake Michigan.
